<!DOCTYPE html>
<html>
    <head>
        <meta charset="utf-8">
        <title>This is my Blog(Yeats)</title>
        <style>
            h1.intro{color: aqua;}
            p.important{color: chartreuse;}
        </style>
    </head>

    <body>
        <h1 class="intro">This is a heading!</h1>
        <p>This parase have'nt class important</p>
        <p class="important">This parase have class important</p>
    </body>
</html>